For example, when information is exchanged between semiconductor integrated circuits (ICs) within an electronic device, a connection is typically made using electrical wiring. As a technique of implementing high-speed signal transmission within the electronic device, for example, low-voltage differential signaling (LVDS) is known. However, with a recent further increase in the volume and speed of transmission data, increased power consumption, increased influence of signal distortion due to reflections and the like, increased unnecessary radiation, and the like, are problematic. For example, when video signals (including image signals) or signals of computer images or the like are transmitted at a high speed (in real time) within a device, LVDS has been reaching a limit.
In order to cope with the problems of the increased speed of transmission data, there is a method of increasing the number of wirings and parallelizing signals to reduce the transmission rate per signal line. However, this results in an increased number of input/output terminals. As a result, it is necessary to make a printed board or cable wiring more complex, increase the semiconductor chip size, and the like. Further, when high-speed/large-volume data is routed using wirings, so-called electromagnetic field disturbance becomes problematic.
All of the problems with the LVDS and the method of increasing the number of wirings result from the transmission of signals by electrical wiring. Therefore, as a technique of solving the problems resulting from the transmission of signals by electrical wiring, a technique of making electrical wiring wireless for transmission is proposed.
For example, as proposed in JP 2005-204221A and JP 2005-223411A, wireless signal transmission within a housing is performed and an ultra-wide band (UWB) communication scheme is applied.